As is my wont, I've updated the comparison figure that I've been showing every month since my "Just in time for (you guessed it) Christmas" post in October. Even then I was struck with the remarkable parallel progression of the 2015-2016 event and the 1997-1998 event, which drove the Temperature of the Lower Troposphere (TLT) to all-time heights. (This data from www.remss.com, Remote Sensing Systems).
As noted last month, the predicted and expected TLT rise began in December. And it continued this January, even as the SST in the Niño 3.4 zone declined just a little, as the event starts to wane. The biggest difference between 2015-2016 and 1997-1998 was that the anomaly went up almost two degrees C in January of 1998, but in January 2016 it only went up about a degree (though it's starting higher, so it's still higher than January 1998's TLT anomaly).
Click on it for bigger view.
I expect it to keep rising. It's now in a basic tie with May 1998 to the second decimal place, slightly lower if you look at the third, and only two TLT anomalies have ever been higher. I think it's a lock to go higher than the second-highest value, which occurred in February 1998. Not sure if it will set a new record or not, but it will come very close if it doesn't. February is going to be really interesting!